high idle and surge, ive tried everything

[UrN2nd]

ok I just got done with my 2g junkyard gst build. I had a crazy high idle and surge like 1700-2500 surge, I couldn't get it to come down. so I turned the biss screw in and it stopped surging and just had a smooth high idle at 1700 rpms. so I did a boost leak test and fixed a few leaks. all very very tiny. got it done. now to set the biss bc I removed it to put a new oring on it. I started it up and it ran quite smooth but still super high. so I was filling the power steering fluid while it ran, then it lost everything and idled about 150-200 rpms and died I figured the biss was in too far so I backed it out. it wouldn't run at all. double checked dsmlink v2 and all my injector calcs were reset to stock so I changed them back to the fic 950 adjustments and put more fuel in the car it was very low. and she started running again. this time idled at 3500 rpms. so I turned the biss in. started it up and then with dsmlink the isc was at 27-29 and learned idle was at 131, then I grounded the 2 boxes in the misc tab so I could set the isc and biss. right when I did the isc went to 9 and the learned idle stayed at 131. no matter what I did biss all the way in or all the way out only my idle changed it never moved the isc position or learned idle not even one point. it didn't surge for about a minute1950 rpms then my idle started surging 1300-1800. I unchecked the grounds on dsmlink and the isc went up to 21. ive tried another maf, I fixed all my leaks, what else could be wrong. why didn't the biss change the isc position when the grounds were activated?

 

[92AWDHX40]

http://www.dsmtuners.com/forums/articles-engine-fuel/191137-how-fix-your-idle-surge-problem.html




start here.

 

[Rsawd95dsm]

Grab and OHM meter and test the ISC motor. This is a good vid on how to check it.

[ame=http://www.youtube.com/watch?v=KibYz21IMA0]DSM ISC motor testing & Replacement - YouTube[/ame]

 

[daplatano91]

Is your coolant system full and bled? These cars tend to surge when coolant level is low.

 

[Armandotech]

If the ISC motor test to be OK then eliminate the FIAV and i'm almost 100% positive that it will fix it, I had the same problem with my galant gs and after trying everything I eliminated the FIAV following road race engineering procedure to do it for free and that fixed the problem, now my car idles at 850 rpms.

 

[UrN2nd]

the coolant system is full. I went out to let it bleed. and the whole time it ran it didn't surge but the idle was still at 1900. another annoying thing. is when I touch the throttle even a tiny bit it revs up to 3400 super fast and stays there for a good 3-4 seconds and then very very slowly comes back down to idle at 1900 rpms. I got pissed and just pulled the throttle body off the car and ill rebuild it tomorrow. any other ideas?

another question my front o2 bounces from .02v to .98 volts that's still good right?

 

[Armandotech]

Those symptoms are pretty much the same that my car had and it was the FIAV

 

[Vdubzr32]

I has the same problem. The solution was to rebuild the TB. One of the gasket seals where worn and was not sealing correctly leading to a leak. Which caused the high idle spike. Hope you solve your#idle problem.